1. Field of the Invention
The present invention relates to a thin profile air purifying filter blower having a thin replaceable filter cartridge that provides enhanced portability and wearability, with the capability to easily replace the filter cartridge even during location of the unit in hot zones.
2. Description of Related Art
Respiratory devices, such as protection masks, also interchangeably referred to herein as face masks or masks, are well known. Civilians, law enforcement, military personnel, fire fighters and other groups of individuals (often referred to as “responders”), as well as others (herein collectively referred to as “users”), wear masks for protection in environments containing harmful, and even hazardous, airborne toxins, and other hazardous or noxious materials. Such toxins and other materials can be hazardous upon exposure to respiratory systems and generally take the form of harmful gases, vapors, aerosols, or particulates. The respiratory hazards may result from various agents, such as nuclear, biological and chemical (NBC) agents.
One type of breathing apparatus, known as a Powered Air Purifying Respirator (PAPR) (also referred to interchangeably herein as “PAPR protection system”), provides for fan-forced positive pressure breathing. PAPR protection systems are typically used in environments in which ambient air is relatively oxygen-rich and where filtering elements are effective in removing contaminants before the air is inhaled by the user. PAPR protection systems typically include a face mask, a filtering element that removes contaminants from the air, a blowing element (interchangeably referred to herein as a “blower”), such as a fan, and a power source that provides operational power to the blowing system. In operation, the fan or other blowing element continuously supplies filtered air to the face mask, where the filtered air replenishes the internal space of the mask. Exhaled air (also interchangeably referred to herein as “spent air”), in turn, is continuously expelled.
Conventional PAPR protection systems have numerous drawbacks. For example, most existing PAPR protection systems do not allow simple and efficient exchange of spent filters for new filters, especially in contaminated environments. One typical hindrance to efficient exchange of filters in conventional PAPR protection systems is the use of threaded connector parts for connecting the replaceable filters. When swapping filters in these conventional PAPR systems, the user must unscrew the old, spent filter from the filter port, discard the used filter, quickly position a new, unspent filter into the filter port to limit exposure to ambient air through the unfiltered filter port, and then thread the new filter into the port. Accordingly, the process of exchanging filters in these systems is both time-consuming and can lead to increased risk of exposure of the user to contaminants, especially if the filter port is even briefly opened or otherwise unprotected.
Due to these drawbacks, PAPR protection systems are limited in their applicability and range of use. For example, the potential exposure to contaminants in ambient air during filter exchange results in conventional PAPR protection systems typically allowing swapping of filters only in safe zones (interchangeably referred to herein as “clean zones”)—those areas where the ambient environment does not contain toxic, harmful, or otherwise to be avoided contaminants. In addition, a conventional PAPR system user may require some level of decontamination prior to replacing the filter within the clean zone.
Another drawback of conventional PAPR protection systems is that the filters themselves are typically bulky and cumbersome. Conventional PAPR protection systems generally have relatively large, projecting cylindrically shaped filter cartridges. For example, when the main body of such a system is worn on a user's back, as occurs in typical use, the cartridges project from the user's body. This configuration results in the systems being bulky and cumbersome, severely hindering user freedom of movement, and often rendering conventional PAPR system use impractical in some environments. For example, a user carrying the bulk of a conventional PAPR system on the back must account for the relatively large size PAPR when entering cramped spaces. As a result, conventional PAPR protection systems have limited usefulness in such limited space environments as vehicles, airplanes, and buildings, and their use may adversely impact maneuverability when used in such applications as combat situations. The user must also account for the added bulk of PAPR systems when performing such actions as rolling, crouching, or ducking.
Yet another drawback of wearing the bulk of a conventional PAPR protection system on the back is the difficulty that this location presents to the user when filter replacement is necessary. Rather than allowing users to carry out such replacement by themselves, the aid of a second person is often required. The inability of users to exchange filters by themselves can thereby increase the risk to the user and decrease range of operation, since these users must rely on a second person typically remote from the working environment when the sometimes urgent need for filter replacement occurs.
Alternatively to wearing the main body of a conventional PAPR system on the back, the bulk of these systems may be attached at the user's waist. While such usage reduces some problems associated with wearing on the back, such as difficulty with unaided replacement of filter cartridges, other problems remain with this approach. For example, whether the main body of the system is located on the back or at the waist, a lengthy connection hose typically must extend from the main body of the system to the air inlet of the face mask. As a result of the need for a lengthy breathing hose, conventional PAPR systems generally have increased airflow loss and greater breathing resistance than systems having short hoses. Moreover, the long breathing air hose has a greater tendency to become kinked, damaged, or entangled during use, potentially both restricting movement of the user and increasing the danger of loss or contamination of air supply.
Accordingly, there remains an unmet need in the art for a PAPR protection system that allows users a wider range of operation and increased ease of use. There is a corresponding similar need for a PAPR system that allows users less limited range of motion and access to areas of limited space. In particular, there is an unmet need for a PAPR protection system that is less cumbersome and bulky than conventional PAPR protection systems, yet maintains the volumetric flow rate of filtered air of conventional PAPR filters. Furthermore, there is an unmet need in the art for a PAPR protection system that allows users to quickly and safely swap filter cartridges (also interchangeably referred to herein as “filters”) in an efficient manner, without subjecting the user to possible dangers that may be present in the ambient environment, while also allowing various components, including the filter cartridges, to be stored and transported effectively and efficiently.